Your Baby typically measures between 12.7cm and 14.6cm from crown to rump and weighs around 155g. You may be able to feel fetal movements now.
Ultrasound image of fetus at 18 weeks gestation.
At week 18 of pregnancy, the fetus typically measures between 12.7cm and 14.6cm from crown to rump and weighs around 155g. The muscles in the chest contract and relax, causing the chest to move up and down, mimicking breathing. The placenta is now not only providing nourishment for the fetus but is also able to filter out harmful toxins, preventing them from affecting the fetus. The placenta is also able to prevent most infections from being transmitted from your bloodstream to the fetus.
Fetal movements are becoming more exaggerated and the repertoire of movements now includes kicking, punching, rolling and twisting. The fetus is now also able to yawn, the hiccups of previous weeks continue and you may now be able to feel them. In addition to this, tiny fingerprints are now developing at the tips of the fingers. If the fetus is female, the vagina, uterus and fallopian tubes are now all in place, and if the fetus is male, it will have distinct genitalia at this stage. In addition to this, teeth are now formed beneath the gums and tooth buds continue to develop.
You may be able to feel fetal movements now – although don’t worry if you can’t – some women don’t feel movement until much later in the pregnancy.
From this point it is recommended that you avoid lying on your back. Your uterus is now large enough to compress a major vein if you lie on your back. This can cause less blood to flow back to your heart and result in dizziness. Lower back pain is a common pregnancy-related symptom at this stage.
Your ever-growing uterus is causing your lower back to curve forward, pushing your abdomen outwards and muscles and ligaments are also being stretched more than ever. Taking warm baths or showers can help to alleviate the aching.
You may also be experiencing cramps – particularly in your lower legs – during the night. Possible causes of these cramps include muscle fatigue or the compression of blood vessels. Stretching your calf muscles before going to bed can help to prevent this. Stretch marks may also now be evident on your belly. Some women don’t get any stretch marks at all, while others have many. Using a good moisturising lotion regularly can help to minimise stretch marks. Thrush is also more common during pregnancy. If you are suffering from thrush, you should seek the advice of your doctor.
Your anomaly scan will be due sometime over the coming weeks. It is usually carried out between 18 and 22 weeks and assesses fetal growth and development and confirms or adjusts the due date. It may also be possible to determine the sex of the baby during this scan; however some hospitals have a policy of not disclosing the sex. It is sometimes not possible to determine the sex due to the position of the fetus during the scan.
Vaginal bleeding is not normal at this stage. Some abdominal pain and backache is normal. Vaginal discharge should be of consistent milky colour and volume. If it is be pink or more voluminous you should see a medical professional. This is particularly true if you have had a previous late miscarriage, operation on your cervix or short cervix. It is also important if you are carrying twins.
The midwife will be able to provide you with advice. The NHS will not routinely be able to offer you an ultrasound scan at this time. NHS hospitals may offer you the routine second scan at 18 weeks but it is better to defer it until 22 weeks when the view of the detailed structure is much better. This is called the anomaly scan.
General midwifery and medical advice is available in private clinics for which you do not require a referral letter. An ultrasound scan at this stage can check the baby for abnormalities and assess it's size. It can also determine the sex of the baby very accurately. If you are concerned about your cervix becoming short or have other concerns about your cervix then an ultrasound scan of your cervix can be reassuring. This gives a better assessment when performed through the vagina.
We had received possible worrying news from our NHS anomaly scan, without much information provided or confirmation. I am so pleased that we came to The Birth Company for reassurance, as we are now extremely happy that everything is fine. Shahrzad was fantastic and went through the whole anomaly scan thoroughly, explaining everything and looking in detail at each area. Nothing was rushed and she took her time to make sure baby was in the correct position to get the best results. We can’t thank her and Dr Gibb enough for the confidence they have given us. Would highly recommend The Birth Company for all scans.
' Professional and reassuring 'Helen Campbell
The sonographer was ready as soon as I arrived, and she was extremely calming, personable and professional. The scan and blood test where efficient without feeling rushed and all very easy. These appointments can feel uneasy and make you feel anxious but I felt reassured and in professional hands the whole time
I saw Kate throughout my first pregnancy and am now doing so again with my second. She is absolutely amazing, she explains everything really clearly, and has answered all sorts of bizarre questions and worries I have had. On top of being clinically excellent she is also just the loveliest person and always a pleasure to see.Sarah Elliott
We had the harmony test with the Birth Company and had a reassurance scan with sonographer Kirsty McGarry who was absolutely lovely and really put our minds at rest. We had been scared by our NHS dating scan and left feeling like there was something wrong. We explained the situation and was treated very professionally and with good care. Also speedy appointments also as I had phone in the morning and got an appointment by afternoon. So thankful.Ashley and Tom
Really friendly, efficient service. Great experience overall. Had the Panorama. My appointment was with Kate who was absolutely fantastic. The results came really quickly. Have a comparison with private healthcare elsewhere and must say that The Birth Company was just how I would like to be treated when I pay for medical services - attentively, calmly, friendly, in a pleasant environment that doesn't look like hospital. Top marks!Anna
' Efficient, friendly and always on hand to provide last minute appointments 'Hannah Murphy
The Birth Company has been excellent, providing timely scans and blood tests during my IVF treatment abroad. Staff are always friendly and extremely efficient. I would highly recommend coming here.
' Professional and friendly 'Lyndsey Dilla
When I first contacted the Birth Company I spoke to Danielle. She was fantastic. She went above & beyond to put me at easy & make the journey from Kent as stress free as possible. Every staff member that myself and my husband have come into contact with have been approachable, professional and friendly. Kate scanned me the first time and put me completely at easy. Lisa on reception is professional and very approachable. Highly recommended
' Highly recommended 'Emelie
Donald was so lovely! I was so nervous as I have a bad history and he was super quick and confirmed my baby's heartbeat as quickly as he could. He spent time showing me the baby and the anatomy and it was the best money I have ever spent! The reception girls were lovely too - considering they deal with babies day in day out they were super excited for me! Thank you so much one and all! If only I lived in London and could have all my scans with you!
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